/*
* Copyright (C) 2017 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#include
#include
#include
#include
#include "blk-mq.h"
#include "blk-mq-tag.h"
struct blk_mq_debugfs_attr {
const char *name;
umode_t mode;
const struct file_operations *fops;
};
static struct dentry *block_debugfs_root;
static int blk_mq_debugfs_seq_open(struct inode *inode, struct file *file,
const struct seq_operations *ops)
{
struct seq_file *m;
int ret;
ret = seq_open(file, ops);
if (!ret) {
m = file->private_data;
m->private = inode->i_private;
}
return ret;
}
static int hctx_state_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "0x%lx\n", hctx->state);
return 0;
}
static int hctx_state_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_state_show, inode->i_private);
}
static const struct file_operations hctx_state_fops = {
.open = hctx_state_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_flags_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "0x%lx\n", hctx->flags);
return 0;
}
static int hctx_flags_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_flags_show, inode->i_private);
}
static const struct file_operations hctx_flags_fops = {
.open = hctx_flags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int blk_mq_debugfs_rq_show(struct seq_file *m, void *v)
{
struct request *rq = list_entry_rq(v);
seq_printf(m, "%p {.cmd_type=%u, .cmd_flags=0x%x, .rq_flags=0x%x, .tag=%d, .internal_tag=%d}\n",
rq, rq->cmd_type, rq->cmd_flags, (unsigned int)rq->rq_flags,
rq->tag, rq->internal_tag);
return 0;
}
static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos)
{
struct blk_mq_hw_ctx *hctx = m->private;
spin_lock(&hctx->lock);
return seq_list_start(&hctx->dispatch, *pos);
}
static void *hctx_dispatch_next(struct seq_file *m, void *v, loff_t *pos)
{
struct blk_mq_hw_ctx *hctx = m->private;
return seq_list_next(v, &hctx->dispatch, pos);
}
static void hctx_dispatch_stop(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
spin_unlock(&hctx->lock);
}
static const struct seq_operations hctx_dispatch_seq_ops = {
.start = hctx_dispatch_start,
.next = hctx_dispatch_next,
.stop = hctx_dispatch_stop,
.show = blk_mq_debugfs_rq_show,
};
static int hctx_dispatch_open(struct inode *inode, struct file *file)
{
return blk_mq_debugfs_seq_open(inode, file, &hctx_dispatch_seq_ops);
}
static const struct file_operations hctx_dispatch_fops = {
.open = hctx_dispatch_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int hctx_ctx_map_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
sbitmap_bitmap_show(&hctx->ctx_map, m);
return 0;
}
static int hctx_ctx_map_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_ctx_map_show, inode->i_private);
}
static const struct file_operations hctx_ctx_map_fops = {
.open = hctx_ctx_map_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void blk_mq_debugfs_tags_show(struct seq_file *m,
struct blk_mq_tags *tags)
{
seq_printf(m, "nr_tags=%u\n", tags->nr_tags);
seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags);
seq_printf(m, "active_queues=%d\n",
atomic_read(&tags->active_queues));
seq_puts(m, "\nbitmap_tags:\n");
sbitmap_queue_show(&tags->bitmap_tags, m);
if (tags->nr_reserved_tags) {
seq_puts(m, "\nbreserved_tags:\n");
sbitmap_queue_show(&tags->breserved_tags, m);
}
}
static int hctx_tags_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct request_queue *q = hctx->queue;
mutex_lock(&q->sysfs_lock);
if (hctx->tags)
blk_mq_debugfs_tags_show(m, hctx->tags);
mutex_unlock(&q->sysfs_lock);
return 0;
}
static int hctx_tags_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_tags_show, inode->i_private);
}
static const struct file_operations hctx_tags_fops = {
.open = hctx_tags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_sched_tags_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct request_queue *q = hctx->queue;
mutex_lock(&q->sysfs_lock);
if (hctx->sched_tags)
blk_mq_debugfs_tags_show(m, hctx->sched_tags);
mutex_unlock(&q->sysfs_lock);
return 0;
}
static int hctx_sched_tags_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_sched_tags_show, inode->i_private);
}
static const struct file_operations hctx_sched_tags_fops = {
.open = hctx_sched_tags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void *ctx_rq_list_start(struct seq_file *m, loff_t *pos)
{
struct blk_mq_ctx *ctx = m->private;
spin_lock(&ctx->lock);
return seq_list_start(&ctx->rq_list, *pos);
}
static void *ctx_rq_list_next(struct seq_file *m, void *v, loff_t *pos)
{
struct blk_mq_ctx *ctx = m->private;
return seq_list_next(v, &ctx->rq_list, pos);
}
static void ctx_rq_list_stop(struct seq_file *m, void *v)
{
struct blk_mq_ctx *ctx = m->private;
spin_unlock(&ctx->lock);
}
static const struct seq_operations ctx_rq_list_seq_ops = {
.start = ctx_rq_list_start,
.next = ctx_rq_list_next,
.stop = ctx_rq_list_stop,
.show = blk_mq_debugfs_rq_show,
};
static int ctx_rq_list_open(struct inode *inode, struct file *file)
{
return blk_mq_debugfs_seq_open(inode, file, &ctx_rq_list_seq_ops);
}
static const struct file_operations ctx_rq_list_fops = {
.open = ctx_rq_list_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
{"state", 0400, &hctx_state_fops},
{"flags", 0400, &hctx_flags_fops},
{"dispatch", 0400, &hctx_dispatch_fops},
{"ctx_map", 0400, &hctx_ctx_map_fops},
{"tags", 0400, &hctx_tags_fops},
{"sched_tags", 0400, &hctx_sched_tags_fops},
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
{"rq_list", 0400, &ctx_rq_list_fops},
};
int blk_mq_debugfs_register(struct request_queue *q, const char *name)
{
if (!block_debugfs_root)
return -ENOENT;
q->debugfs_dir = debugfs_create_dir(name, block_debugfs_root);
if (!q->debugfs_dir)
goto err;
if (blk_mq_debugfs_register_hctxs(q))
goto err;
return 0;
err:
blk_mq_debugfs_unregister(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister(struct request_queue *q)
{
debugfs_remove_recursive(q->debugfs_dir);
q->mq_debugfs_dir = NULL;
q->debugfs_dir = NULL;
}
static int blk_mq_debugfs_register_ctx(struct request_queue *q,
struct blk_mq_ctx *ctx,
struct dentry *hctx_dir)
{
struct dentry *ctx_dir;
char name[20];
int i;
snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
ctx_dir = debugfs_create_dir(name, hctx_dir);
if (!ctx_dir)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(blk_mq_debugfs_ctx_attrs); i++) {
const struct blk_mq_debugfs_attr *attr;
attr = &blk_mq_debugfs_ctx_attrs[i];
if (!debugfs_create_file(attr->name, attr->mode, ctx_dir, ctx,
attr->fops))
return -ENOMEM;
}
return 0;
}
static int blk_mq_debugfs_register_hctx(struct request_queue *q,
struct blk_mq_hw_ctx *hctx)
{
struct blk_mq_ctx *ctx;
struct dentry *hctx_dir;
char name[20];
int i;
snprintf(name, sizeof(name), "%u", hctx->queue_num);
hctx_dir = debugfs_create_dir(name, q->mq_debugfs_dir);
if (!hctx_dir)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(blk_mq_debugfs_hctx_attrs); i++) {
const struct blk_mq_debugfs_attr *attr;
attr = &blk_mq_debugfs_hctx_attrs[i];
if (!debugfs_create_file(attr->name, attr->mode, hctx_dir, hctx,
attr->fops))
return -ENOMEM;
}
hctx_for_each_ctx(hctx, ctx, i) {
if (blk_mq_debugfs_register_ctx(q, ctx, hctx_dir))
return -ENOMEM;
}
return 0;
}
int blk_mq_debugfs_register_hctxs(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
if (!q->debugfs_dir)
return -ENOENT;
q->mq_debugfs_dir = debugfs_create_dir("mq", q->debugfs_dir);
if (!q->mq_debugfs_dir)
goto err;
queue_for_each_hw_ctx(q, hctx, i) {
if (blk_mq_debugfs_register_hctx(q, hctx))
goto err;
}
return 0;
err:
blk_mq_debugfs_unregister_hctxs(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
{
debugfs_remove_recursive(q->mq_debugfs_dir);
q->mq_debugfs_dir = NULL;
}
void blk_mq_debugfs_init(void)
{
block_debugfs_root = debugfs_create_dir("block", NULL);
}